1. Field of the Invention
The present invention relates to a light emitting module and a lighting unit. More particularly, the invention relates to a light emitting module using a semiconductor light emitting unit as a light source, and a lighting unit.
2. Description of Related Art
In a lighting unit for a vehicle such as a headlamp for a vehicle, the formation of a light distribution pattern with high precision is required for safety. The light distribution pattern is formed by an optical system using a reflecting mirror or a lens. For example, JP-A-6-89601 Publication (Pages 3 to 7, FIGS. 1 to 14) discloses this type of system. In recent years, moreover, a semiconductor light emitting unit has been utilized as the light source of the headlamp for a vehicle.
In the case in which a semiconductor light emitting unit is used as the light source of a lighting unit, it is necessary to efficiently cause the semiconductor light emitting unit to emit a light, thereby satisfying a light quantity level required for the lighting unit. In order to efficiently cause the semiconductor light emitting unit to emit a light, it is necessary to prevent a reduction in luminance due to a heat. Since the semiconductor light emitting unit has a small size, it has a smaller light emitting region than that in a conventional light source. Accordingly, in order to form a light distribution pattern with high precision, the relative positions of the optical system, such as a lens or a shade, with the semiconductor light emitting unit must be managed with high precision.